lentigo maligna melanoma


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Related to lentigo maligna melanoma: Acral lentiginous melanoma, Superficial spreading melanoma

melanoma

 [mel″ah-no´mah]
a tumor arising from the melanocytic system of the skin and other organs. When used alone, the term refers to malignant melanoma.
acral-lentiginous melanoma an uncommon type of melanoma, although it is the most common type seen in nonwhite individuals, occurring chiefly on the palms and soles, and sometimes involving mucosal surfaces, such as the vulva or vagina. The characteristic lesion is an irregular, enlarging black macule, which has a prolonged noninvasive stage.
lenti´go malig´na melanoma a cutaneous malignant melanoma found most often on the sun-exposed areas of the skin, especially the face. It begins as a circumscribed macular patch of mottled pigmentation, showing shades of dark brown, tan, or black (lentigo maligna or melanotic freckle of Hutchinson), and enlarges by lateral growth before dermal invasion occurs. This type seems to be the least aggressive form of malignant melanoma.
malignant melanoma a malignant skin tumor, usually developing from a nevus and consisting of dark masses of cells with a marked tendency to metastasis. It is not common, but its incidence is increasing and it is the most aggressive type of skin cancer. It arises from pigment- (melanin-) producing cells and varies in course and prognosis according to type; types include superficial spreading melanoma, nodular malignant melanoma, and lentigo maligna melanoma. In general, the superficial lesions can be cured by surgical excision of the mole and adjacent tissues. Deeper lesions tend to metastasize rapidly through the lymphatic and circulatory systems. In some cases the condition has a genetic component. Early detection and skin protection are key in its control.

lentigo maligna melanoma

a neoplasm developing from Hutchinson's freckle on the face or other exposed surfaces of the skin in elderly patients. It is asymptomatic, flat, and tan or brown, with irregular darker spots and frequent hypopigmentation. It is one of the major clinical types of melanoma and occurs in 10% to 15% of melanoma patients. See also nodular melanoma, superficial spreading melanoma.
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Lentigo maligna melanoma
References in periodicals archive ?
However, the prognosis of lentigo maligna melanoma overall appears to be equal, or slightly better, than that of other melanoma subtypes.
Increasing incidence of lentigo maligna melanoma subtypes: northern California and national trends 1990-2000.
Mohs micrographic surgery for lentigo maligna and lentigo maligna melanoma.
Questions about the accuracy of reading frozen sections of melanocytic tumors have generated controversy about using Mohs surgery to treat lentigo maligna and lentigo maligna melanoma.
Whether clinically hyperpigmented or amelanotic, some authors (26) consider lentigo maligna to be an earlier atypical melanocytic proliferation (hyperplasia) on chronically sun-damaged skin histologically distinct from melanoma in situ, lentigo maligna type, the preinvasive form of lentigo maligna melanoma.
The first 4 Crowson/Magro/Mihm histologic categories (1-4) include lesions raising a histologic differential diagnosis of severely atypical/dysplastic nevus or nevus of special anatomic site (genital, milk-line, acral, etc), and superficial spreading or lentigo maligna melanoma (categories 1-4) are by far the most common examples of histologically borderline melanocytic tumors encountered in routine practice.
Four primary groups have been traditionally proposed based on a combination of clinical and pathologic features: superficial spreading melanoma, nodular melanoma, lentigo maligna melanoma and acral lentiginous melanoma.
2,5,9) Conversely, lentigo maligna melanoma is limited to the skin areas most exposed to sunlight and is characterized by longer intraepidermal or radial growth phases (long RGP) (Figure 1).